Method of dyeing woolen and other nitrogenous textile materials



Get. 16, 1945. H. J. WALTER METHOD OF DYEING WOOLEN AND OTHER NITROGENOUS TEXTILE MATERIAL 2 Sheets-Sheet l INVENTOR 640F040 J Wzrzfi.

ATTORNEY Filed Dec. 50, 1943 06%. 16, 1945. J WALTER 2387,20

METHOD OF DYEING WOOLEN AND OTHER NITROGENOUS TEXTILE MATERIAL Filed Dec. 30, 1943 2 Sheets-Sheet 2 INVENTOR 626F040 cf kfizrz a ATTORNEY Patented Oct. 16, 1945 METHOD OF DYEING WOOLEN AND OTHER NITROGENOUS TEXTILE MATERIALS Harold J. Walter, Uxbridge, Mass., assignor to Uxbridge Worsted 00., Inc., Uxbridge, Mass., a corporation of Massachusetts Application December 30, 1943, Serial No. 516,193

11 Claims.

This invention relates to the dyeing of textile materials, and is a continuation-in-part of my co-pending application Serial No. 423,431, filed December 18, 1941.

Heretofore the dyeing of nitrogenous fibers or unions thereof for textile uses has been carried out according to long established practice at temperatures below 212 F., or in temperature ranges having 212 F. as the upper limit. This is true not only of wool and worsted cloth, yarn, and top, but also of nitrogenous fibers generally (both natural and artificial, and including animalized fibers, and fibers of polyamide type).

In a few instances dyeing has been undertaken in a kier where the fibers have been exposed to temperatures in excess of 212 F. for a long period of several hours. I do not know of any instance where nitrogenous textile fibers have been treated in this way, but in any event it is well known that exposure to a high temperature for the long period of time incident to kier treatment injures and destroys the strength of fibers particularly nitrogenous fibers and renders them unfit for textile uses. Furthermore kier treatment is a batch operation which has the several disadvantages referred to below.

Accordingly it is an object of the invention to provide a simple, eflicient and practical method of accelerated dyeing of nitrogenous textile fibers and unions thereof.

Another object is to provide a method by which a desired shade may be duplicated for a given nitrogenous cloth or fiber more readily and with more accurate results than has heretofore been possible.

Another object is to provide a method whereby a length of nitrogenous cloth or textile fibers or yarn may be dyed with a period of contact be-' tween the cloth, fibers, or yarn and the dye solution which is much shorter than has heretofore been used in the trade.

Another object is to provide a method of dyeing basic nitrogenous textile materials in which the dye solution may be efilciently employed and conserved while employing dye concentrations on the order of from two to four percent of the dye solution by volume, or even higher.

It has heretofore been customary in dyeing woolen or worsted cloth, top, or yarn and other nitrogenous fibers and strips of cloth to employ a batch operation wherein the dyeing vat has been loaded with material for a long period of several hours. A batch operation is not only inefficient in time but the packing and pressing of material in the dyeing chamber creates problems of uneven dyeing of the material which are exceedingly hard to solve.

Accordingly it is a further object of this invention to overcome the disadvantages inherent in dyeing wool-and woolen materials and other nitrogenous textile materials, and materials comprising wool or other nitrogenous textile materials as heretofore carried out and to provide a simple, practical method for the dyeing of wool and woolen materials and other nitrogenous textile materials and materials comprising wool or other nitrogenous textile materials, continuously, and in open form.

Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the several steps and relation and order of each of said steps to one or more of the others thereof, all as will be pointed out in the following description, and the scope of the application of which will be indicated in the following claims.

The invention will best be understood if the following description is read in connection with the drawings in which,

Figure 1 is a side view, partly in cross section, of means by which the method disclosed herein may be performed;

Figure 2 is a top plan view taken on the line 2-2 of Figure 1;

Figure 3 is an enlarged detail view of the upper part of one end of the chamber and air-sealing means shown in Figure 1, and is also a side elevation partly in cross section;

Figure 4 is a vertical, transverse section taken on the line 4-4 of Figure 3;

Figure 5 is a side view similar to Figure 1 showing a plurality of aqueous baths in a closed chamber; and

Figure 6 is a, view similar to Figures 1 and 4 showing a plurality of aqueous baths one of which is outside of the closed chamber.

Where the term cloth is used herein it will be understood to include any continuous length of cloth, top and the.like.

In Figures 1, 4 and 5 a length of material M in open form is shown passing through an aqueous bath It! contained in a closed chamber II. As will be explained the desired dye may be introduced into this bath separately from the cloth as illustrated in Figure 1, or it may be padded onto the cloth either outside or inside chamber II as illustrated in Figures 5 and 6 respectively and carried with the cloth into bath Hi. In

either case the cloth is'pa-ssed through the aqueous bath ID in the presence of the desired dye, the bath being heated to a temperature in excess of 212 F. as will be pointed out. The length of material passes into and out of chamber H through wall opening or dies, l2 and I3 respectively, which are sealed-in any suitable practicable way to provide a chamber in which temperatures on the'order of 295 F. or even higher may be maintained. As illustrated herein the sealing means of each of the wall openings l2 and I3 comprise a roll M, which preferably has a facing of rubber or rubber-like material, and has a resilient surface, and thepower rolls l5 and 16. The power rolls l5 and 16 are respectively supported on shafts I1 and I8 each of which extends through bearings IS in the respective side walls of chamber H, and a gear 20 may be provided at one end of each of said shafts respectively for connection to any suitable source of power.

The roll H of each set of closure rolls is mounted in slots or slideways 2| provided in the portions of the chamber wall which as shown herein are obliquely related to the body of the chamber H at the top of its ends respectively. A removable closure member 22 is provided at the top of each of said end portions of the chamber II which may be removed to permit withdrawal of roll I 4 from chamber Means for adjusting the position of each roll I4 along the slideway 2| is provided and may consist of adjusting screw means 23 extending through the removable closure member 22 into contact with the bearing member 24 provided on the trun- 'nions 25 at the ends of roll H.

The rolls l4, I5, and i6 are disposed in a triangular arrangement in which both rolls l5 and l6 are positioned to press against the resilient face of roll I4 and as has been explained the latter may be adjusted toward or away, from rolls l5 and I6 as may be required.

Cross seal members 26 are provided, abutting against rolls l5 and I6 respectively. As illustrated herein the cross sealing means comprises any suitable compressible material" which is adapted to expand at right angles to the pressure applied by the tubular portion 21 which is preferably of a resilient material such as rubber thereby providing an efiective sealing between itself and the roll against which it is pressed. The ends of the tubular portion 21 of each cross seal member 26 may be supported at its ends upon preferably rigid supporting membars 28 extending through the respective side walls of chamber oneof which may, if desired, be hollow so that air may be introduced therethrough into the said tubular portion.

The cross sealing means for roll l5-is shown herein as being supported in a bracket 29 extending inwardly from the end wall of chamber H, and the cross sealing means for roll I6 is shown as being supported in a bracket 30 depending from the upper portion or top of chamber As stated above the trunnions 25 at the ends of ,each roll I4 are slideably seated in the slideways 2| provided within chamber The ends of shafts l1 and I8, for rolls l5 and I6, respectively, which extend through the opposite side walls of chamber I, may be provided at their ends with wear rings 3| to take the wear of the sealing material pressed against them. The sealing material may comprise a metal ring 32, a tubular, preferably resilient, sealing ring 33,

which may ifdesired be pneumatic in character, and the metal ring 34, interposed between the end wear ring 3| and the wall of chamber II which may be recessed to provide a seat for the sealing means.

A continuous strip of material M passes into chamber H in open form through the aforesaid wall opening or die l2, between roll l4 and power roll I5, over idler 35 into the aqueous solution S contained in bath I0, under idlers 36 and 31 in the solution S, over idler 38, and out of the chamber between resiliently faced roll l4 and power roll l5, of the set of rolls closing wall opening l3, and through the wall or die opening I3, over idler 39, into a rinsing bath where any dye not taken up by the material is washed oil. The rinsing bath is identified as 40 and rollers 4|, 42, 43 and 44 are shown by which the material M may be guided through the rinsing bath.

Coils 45 are provided in the bath l0 through which steam is circulated to heat the aqueous bath solution S to the desired temperature, and the branched conduit 45a is preferably provided by which compressed air may be introduced at various points under the surface of the aqueous solution in bath III to agitate the solution as an aid in promoting uniformity of the solution.

A reservoir 46, which may have a removable top 41, and communicates with the. bath l0 through conduit 48 is illustrated as positioned for convenience at a point outside chamber H. To insure flow from the reservoir to the bath I0 a compressor 49 is provided connected by conduit 50 to pressure tank 5| which in turn is connected to reservoir 46 by conduit 52. In each of the conduits 48, 50, and 52 a valve V is provided for regulating the pressure in the system and the flow between the reservoir 46 and the bath l0. Any substance to be mixed into the aqueous bath Ill may be prepared in reservoir 46. This substance will be a selected dye if the dye is to be introduced into bath I ll separately from the material to be dyed, or, if the dye is to be padded onto the material before it reaches bath I0 and introduced into bath ||l along with the material to be dyed, the substance will be an agent to prevent bleeding of the dye from the material in bath l0 without substantially impeding the penetration of the dye into the material.

In-the modification of the invention illustrated in'Figure ,1 in which the dye is introduced into the aqueous bath separately from the cloth, the dye solution may be prepared in reservoir 46, before the start of a run of material. For this purpose a small amount of water may be added to the chosen dye to form a paste which is then mixed with water in the reservoir. The volume of dye solution prepared will of course be determined by the amonut of material comprising the run. When the dyeing solution has been prepared valve V in conduit 48 is opened, compressor 49 is actuated and valves V in conduits 50 and 52 are opened if they are not already opened. In some cases it-may be desirable to keep a constant fiow of dye solution from the reservoir to the dye bath throughout the entire period of the run. Thus if any variation in the concentration of the dye solution in the dye bath should occur it may be readily compensated for by a corresponding change in the concentration of the dye liquor in the reservoir. On the other hand it may sometimes be desirable to supply the entire contents of the reservoir to the dye bath at the start of a run and to mix another dye solution preparatory to another run while the first run is being made. This may be desirable where two or more comparatively short runs are to be made.

Suflicient dye material is supplied to the reservoir so that a solution of the desired concentration and pH may be supplied to the dye bath III to maintain therein a solution of substantially constant concentration and pH throughout the whole dyeing operation.

In the embodiment of my invention illustrated in Figures 5 and 6 the procedure will be the same as that described above in connection with the modification of the invention described in Figure 1 except that the selected dye, instead of being introduced into bath I separately from the cloth, as for example by being initially mixed in reservoir 46 and introduced into'bath-III through conduit 48, is padded onto the cloth before the cloth is introduced into bath II], but in all the embodiments of the invention illustrated herein, in Figures 1, 5 and 6, the penetration of the dye into the material being dyed, and the chemical union between the dye and the material, is accomplished and accelerated within chamber I0, like numerals being employed in all of the drawings to indicate like parts. The dye may be padded onto the material in any suitable way as for example by being brought into contact with a dye solution long enough to become soaked with the dye solution, as for example by being initially passed through a preliminary bath of dye solution P contained in dye vat 53. As illustrated in Figure 5 dye vat 53 is contained within closed chamber II whereas in Figure 6 dye vat 53 is illustrated as positioned exteriorly of chamber ll.

As illustrated the vat 53 may be of substantially smaller dimension than vat II] with the result that the volume of dye solution left in vat 53 after the completion of a run of material will be comparatively small. Thusthe preliminary step of padding the dye onto the material to be dyed effects an economy of the dye stuff employed, and, particularly in the case of short runs of material, a substantial saving may be eifected.

It will be noted that where the padding step is performed exteriorly of chamber II the dye will be subjected to the temperatures in excess of 212 F., used in chamber II, only for the time required for a given point on the cloth to move through chamber II, and this is an exceedingly short period which for the purpose of example and illustration of the working of my invention is described herein as requiring a period of time of say from one-quarter minute to five minutes depending on the material being dyed and the shade desired.

Where the padding is performed in a dye vat 53 contained within chamber II the small volume of dye vat 53 results in the dye molecules being exhausted and removed from vat 53 rapidly and frequently, so that there is a high turn over of the dye molecules introduced into vat 53, and the average time that a dye molecule is present in vat 53 is very short, and the total amount of time that the average dye molecule is present within chamber II, ,and passing both through dye solution P in vat 53 and through the aqueous solution S in bath I0, is sufiiciently short to permit substantially all dyes to be used without danger of impairment by exposure to the high temperatures employed in chamber I I.

When the dye is initially padded onto the cloth and introduced into the aqueous solution S in bath I0 along with the cloth an agent or from the cloth.

I the cloth, is introduced into bath I0 separately An example of the successful practice of my invention employing a preliminary padding step is as follows:

Dye was deposited on a piece of worsted cloth by soaking the cloth with a 3% solution of Calcocid Milling Red 3R. conc. (C. I. 275) using a padding machine of known construction, and such as is illustrated in Figures 5 and 6; As a result of the padding step the colorwas only deposited on the surface of the cloth and did not develop the true shade or fastness properties of this dye. The padded cloth was then introduced into closed chamber I I and into bath I 0 containing a solution consisting of 30 parts of sodium acetate and 10.6 parts of acetic acid along with 3 parts of diamyl sodium sulfcsuccinate in 300 parts of water, heated to a temperature of 250 F., and the cloth was passed through bath Ill so that the period of contact between a given fiber in the cloth and the highly heated solution S was 50 seconds. After the dyeing step in bath I 0 the material passed out of the closed chamber and through a rinsing bath as described in connection with the embodiment of the invention disclosed in Figure 1, and also Figures 5 and 6. The dyed cloth had a bright red shade showing a very satisfactory penetration of the dye into the cloth, and the cloth had and the fibers of the cloth had been accomplished.

A selected agent or agents may, if desired, be introduced into bath ID from an external mixing chamber and for this purpose an assembly of a mixing chamber or reservoir, a com pressor, a pressure tank, and suitable interconnecting conduits may be provided, if desired, as is illustrated in connection with Figure 1, and a conduit 48a is indicated in connection with bath I0 in Figures 5 and 6 through which a selected agent to prevent bleeding of the dye from the material may be introduced.

Similarly it will be understood that means for supplying dye into vat 53, as through conduit 48b may be provided, irrespective of whether vat 53 is positioned within, or externally of chamber II, I

and, at 4517 means for agitating dye solution P, are'indicated, which means if desired may be 4 similar to branch conduit 45a used for introducand will pass out of vat 53 and-between the padding rolls 51a and 51b, and will then be introduced into an aqueous bath S in bath II'I, passing under rollers 36 and 31 submerged in solution S, and will pass out of the aqueous bath S over roller 38 and through exit rollers into a rinsing bath as described in connection with Figure 1. And in the embodiment of the invention illustrated in Figure 6 the strip of material will initially be passed into a dye vat 53 located exteriorly of chamber II, being guided over a roller 58 into solution P- in vat 53, and after being guided through solution P under rollers 59 and 60 submerged therein it will pass out of bath P and between the rolls Na and Bib and into chamber II where itwill passthrough the entrance sealing rollers and into and through aqueous solution S, and out of chamber ll into and through a rinsing bath in the manner described in connection with the embodiment of the invention shown in Figure 1.

Where the dye is initially padded onto the material to be dyed the material is preferably kept submerged in solution S in bath l after it has been initially introduced into solution S until the penetration of the dye into the material, and the chemical bonding of the dye with the material, has been completed, in order to prevent streaking of the material and non-level dyeing. It has been found that if the material padded with dye is run in and out of the aqueous solution 8 the dyeing result obtained is not as satisfactory as where the material is kept submerged within solution 8 until the theoretically opposed dye penetration and dye bonding actions have been fully completed. It is thus preferred,

' where the dye is initially padded onto the material to maintain the material sumberged in the solution S during the greater portion of the period or time it is passingthrough chamber H, and especially to keep it submerged in solution S, after it has been initially introduced into solution S, until the penetration and bonding actions are completed.

Irrespective of how the dye is introduced into aqueous solution S in bath I0 I raise the temperture of the aqueous solution in the bath ill to a temperature which is above, preferably well above, 212 F. The particular temperature above 212 F. selected will depend upon the kind of fabric being dyed and the shade desired, as explained below. I'lead the material end to end,

the concentration of the dye solution used to give.

' in open continuous form, into the air-sealed the shade desired under theaforesaid constant conditions but it will be understood that the concentration may be kept constant if desired, as may be the case in some instances, and'one or more of the other factors of temperature, pressure and period of contact mat be varied.

I have found that at the high temperatures used in my process I am able to pass a strip of cloth through the closed chamber H at a rate of more than twenty-five yards per minute, keeping in less than two hours.

Accordingly to my method there is no upper limit, that I know of, to the temperature which may be employed except the limit imposed by the limitations of the apparatus used for increasing the speed of travel of the material. With my present apparatus I have obtained good results using temperatures to and in excess of 295 F.

To obtain the full benefit of my process the highest practical temperature should be employed, and the period of contact of thematerial with the aqueous solution S in bath I0, should be fixed as the minimum period required to give the desired shade using the maximum dye concentration which is economical. The minimum period required to give the desired shade using a temperature within the range of from 220 F. to 295 F. will be from say five minutes to a quarter of one minute.

The lower limit of the temperature range is more difilcult to fix, because, although higher temperatures are preferable it is possible to obtain a measureable acceleration in the rate of penetration and chemical bonding employing temperatures which while well above 212 F. are nevertheles lower than the optimum temperature rang for the fiber to be dyed according to my method. Thus, for example, I have found that while the preferred lower limit of the range for treating lengths of woolen or worsted material or wool fibers, is approximately 240 F., improved useful practical results may be obtained with temperatures down to possibly 220 F. particularly if the wool material is pretreated by wetting it out with acid such as acetic acid, or if the period of contact between the material being dyed and the aqueous bath, in the presence of the selected dye, is prolonged, although thi is undesirable because of the greater time, or the increased size of bath ID, or both, which is required.

For the union dyeing of wool I prefer to use temperatures having a range well above 212 F., preferably employing a temperature on the order of 260 F. in a range having 240 F. as its lower limit, but in some cases having 220 F. as its lower limit according to the percent of wool in the cloth being dyed.

As an illustration of the results obtained by the employment of the high temperatures of my method on cloth being continuously and rapidly moved through an aqueous bath in, into which the dye was introduced separately from the cloth, I give the results tabulated below from operations in which there was used in each instance the same'dark blue dye and the same pressure but diflerent' temperatures:

' In both of these operations the period of contact between solution S and the material at a given point was 0.36 minutes, and the concentration of the dye in solution S was 2.37 by volurne.v By the first operationa privative dyeing was obtained i. e. some dye had penetrated but the material had not absorbed anywhere near the'amount. of color required. The second operation produced full shade dyeing.

In the practice of my invention it is possible and practical to use higher dyeconcentration than can be used in a batch operation, thus further accelerating the dyeing operation; for example, 'I have obtained excellent results using dye'solutions in which dye was from 2% to 4% of the solution by volume; according to the shade desired, at temperatures from 220 F.-290 F. butI do not wish to be limited to this range 'method I may use all dyes.

which may be considerably widened according to the temperature used and the shade desired.

Generally speaking, in the performance of my Some of the dye stuffs which I have used, introducing the dye separately from the cloth, with very satisfactory results, in concentrations ranging from 2% to 4% by volume at temperatures above 239 F., and for a period of contact with the material of one-half a minute or less, are the following: Pontacyl Fast Blue SB 209, Pontacyl Black RC (no number), Pontacyl Fast Carmine 6B, 57,

Pontacyl Dark Green B 247,- and Neutral Red MG -(Calcocid Fast Red A, 176). I have also obtained good results using direct dyes, particularly in dyeing mixtures of wool and other fibers.

Among the dyes I have found satisfactory for dyeing a mixture of wool and non-woolen fibers are the following:

Calcomine Navy Blue R (no number) Do Black BTCW 401 Calcodur Brown BRL (no number) Calcomine Red F 419 Calcodur Yellow N 814 Do Orange GL 653 Do Green BL (no number) In dyeing unwoven fibers, such, for example, as "top or a mixtureof fibers, a conveyor of any suitable construction, such, for example, as an endless conveyor, may b provided, to receive a sliver from the entrance die and support and conduct it down into and under the surface of the dye solution and upwardly to the exit die. Obviously various means may be provided for supporting the fibers in the dye bath and bringing them into contact with both the dye bath and the rinsing bath.

In carrying out my method I prefer to employ a closed chamber having transparent side walls or windows through which the operations within the chamber may be viewed. In order to resist clouding of the transparent side walls or windows by steam I prefer to maintain within the closed chamber a pressure sufiiciently above the pressure of saturated steam at the temperature employed to resist the formation of steam and to maintain visibility. This may be readily accomplished by introducing compressed air into the closed chamber l l, as for example through branched conduit 45a, and I have successfully maintained visibility within chamber I] using a pressure of approximately 50 lbs. per square inch for-temperatures from 240 to 280 F. If higher temperatures are used a corresponding increase in pressure is desirable to maintain visibility without clouding.

It will thus be seen that there has been provided by this invention a method in which the various objects hereinabove set forth together with many thoroughly practical advantagesare successfully achieved. As various possible embodiments might be made of the features of the above invention and as the art herein described might be varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

What I claim is:

1. The method of dyeing material comprising nitrogenous textile material which comprises running a length of material in open width through an aqueous bath in the presence of a selected dye,

said bath being heated substantially above 212 F., under pressure, the dye being substantially completely fixed on the material during the period of contact of the material with the said bath, and no further ageing being necessary.

2. The method disclosed in claim 1 in which the period of contact between the said aqueous bath and the material is on the order of from 0.25 minutes to 5 minutes.

3. The method disclosed in claim 1 in which the said aqueous bath is heated within a range having a temperature on the order of 295 F. as its upper limit.

.4. The method of dyeing material comprising notrogenous textile material which comprises running a length of material in open width through an aqueous bath in the presence of a selected azo dye, said bath being heated substantially above 212 F., under pressure, and the dye being substantially completely fixed on the pletely fixed on the material during the periodof contact of the material with the said bath, and no further ageing being necessary.

6. The method of dyeing material comprising nitrogenous textile material which comprises running a length of material in open width through an aqueous bath in the presence of a selected dye, said bath being heated'to within a high temperature range having a temperature on the order of 240 F. as its lower limit, under pressure, and the dye being substantially completely fixed on the material during the period of contact of the material with the said bath, and no further agein being necessary.

7. The method of dyeing woolen material and material comprising wool which comprises running a length of material in open width through an aqueous bath in the presence of a selected dye, said bath being heated substantially above 212 F., under pressure, and the dye being substantially completely fixed on the material during the under pressure, and the dye nitrogenous textile material which comprises pad-- ding a selected dye onto a length of material and running the length of material in open width through an aqueous bath heated substantially above 212 F., under pressure, the dye being substantially completely fixed on the material during the period of contact of the material with the said bath, and no further ageing being necessary.

10. The method of dyeing material comprising nitrogenous material which comprises run- 11. In a method 01' dyeing material comprising wool, nylon, silk, and other nitrogenous fibers the step which comprises running a length of the material in open width through an aqueous bath of dye solution heated substantially above 212 F. under pressure to substantially completely fix the dye on the material.

HAROLD J. WALTER. 

